Liquid-Liquid Phase Transition in Supercooled Silicon

TL;DR

This review discusses the metastable liquid-liquid phase transition in silicon, comparing simulation models with experimental data, and exploring structural, dynamic, and thermodynamic properties relevant to phase behavior.

Contribution

It provides a comprehensive synthesis of experimental, theoretical, and simulation studies on liquid silicon, critically assessing classical potentials against ab initio results.

Findings

Classical empirical potentials have limitations in accurately modeling silicon's behavior.

Ab initio simulations align better with experimental data than classical models.

Thermodynamic properties are sensitive to model parameters.

Abstract

We present a review on the study of metastable silicon, primarily focusing mainly on the aspects of liquid-liquid transition, critical point and phase behaviour, structural and dynamic properties of liquid phase as well as crystal nucleation. We begin with an extensive survey of the investigations of liquid silicon pursued over three decades, with salient experimental, theoretical and simulation results. Following which we present various scenarios put forward to rationalize the density and related anomalies often observed in water and other network forming liquids. After which we present the more recent investigations (both simulation and experimental works) of the phase behavior of Silicon. Since a significant part of metastable silicon work is on a classical empirical potential an important question to address is the reliability of this potential in describing the behavior of silicon. To provide a critical assessment of the applicability of classical simulation results to real silicon we present a comparison of the structural, dynamical, and thermodynamic quantities obtained from the SW potential with those from ab initio simulations and with available experimental data. We also discuss the sensitivity of the thermodynamic properties to model parameters.